Android Question Clear Bluetooth UART Example


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I am trying to establish serial comms with a BLE Bluetooth module using the Transparent UART Service.

So far after reading all the Bluetooth related posts, I can't seem to find any clear working example.

I have the Bluetooth Chat example project Bluetooth.B4A which when searching for devices takes a long time to find the module, then when connecting I get:

Error connecting:
read failed, socket might closed or
timeout, read ret: -1

I don't see where on the APP you put the UUID either?

Also I have tried the BLE Example BLE.B4A which seems to just have two sliders and not even a way to connect to devices.

I'm trying to get some kind of a starting point where I am able to pass data between my android device and a BLE RN4871 using transparent UART.


Anyone able to tell me where I'm going wrong?

Last edited:


Active Member
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I am very new to B4A and this is a small part of a very large project, I don't have lots of time to spend learning from the ground up.

I've picked B4A as a platform moving forward as it looked like I'd be able to easily understand it coming from a Basic background of more than 15 years.

I am also very new to Bluetooth with zero experience on the Android side, I expect to learn all about it as I go but I could really do with some help tying in this connection BLE_Example with sending and receiving serial data with my BLE device.

Once I've done this I would be very happy writing a detailed guide and project example once it's working.

If anyone has already done a serial data app with a BLE device I would very much appreciate any help.



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